多普勒超声观察运动前后分流量变化 评估房缺患儿心肺储备功能

目的探讨多普勒超声检测先天性心脏病房间隔缺损（ASD）患儿运动前后分流量的改变对评估心肺储备功能的价值。方法对35例先天性ASD患儿,运动前股动脉取血2 ml进行血气分析;采用经胸多普勒于剑下四腔心和胸骨旁四腔心切面观测房间隔缺损大小,测量分流量;同时以M型超声测量左心室射血分数、肺动脉压、主肺动脉根部内径等指标。运动后立即取动脉血做血气分析,同时测量上述各项指标改变。术后48-72 h检测肺动脉压、血氧分压、主肺动脉根部内径及左心室射血分数等指标。结果运动后缺损处分流量较运动前减少（P〈0.05）,肺动脉压有不同程度的升高、动脉血氧分压下降（P均〈0.05）;左心室射血分数和主肺动脉根部内径无明显变化。术后48-72 h检测肺动脉压25例下降明显,10例下降不明显,动脉血氧分压等指标与运动后相比差异无统计学意义。结论多普勒超声检测先天性ASD患儿运动前后分流量的变化可间接反应其心肺功能储备状况,为临床手术适应证的选择及预后判断提供理论依据。

Evaluation of heart-lung reserve function of ASD with the measurement of shunt volume pre- and post exercise

Objective To evaluate heart-lung reserves in children with atrial septal defect（ASD） with Doppler ultrasound measurement of shunt volume pre-and post exercise.Methods Thirty-five children with congenital heart ASD underwent Doppler ultrasonography.The femoral artery blood of 2 ml was got for blood gas analysis before exercise,then all the patients were examed with transthoracic Doppler under the xiphoid porcess in the four-chamber heart and parasternal four-chamber view to observe the size of atrial septal defect,and shunt volume was measured.Left ventricular ejection fraction,pulmonary artery pressure,the main pulmonary artery diameter and other indicators were measured with M-mode ultrasound.After exercise,arterial blood gas analysis was done,and all the above indicators were measured again.Forty-eight to seventy-two hours after operation,pulmonary artery pressure,blood oxygen,the main pulmonary artery diameter and left ventricular ejection fraction were measured.Results Post exercise,the shunt of defect reduced,pulmonary artery pressure increased,and PaO2 dropped down compared with those of pre-erercise（P〈0.05）,while no significant changes of left ventricular ejection fraction and pulmonary artery diameter were detected.The pulmonary arterial pressure decreased quickly in 25 patients,but dropped down slowly 48-72 h after operation in 10 patients.Compared with pre-exercise,the blood oxygen changed significantly.Conclusion Doppler ultrasound measurement of shunt volume pre-and post exercise may indirectly show the heart-lung reserve status of patients with ASD,being helpful to the choice of surgery and the predicting of prognosis.